IRR Calculator
Calculate the internal rate of return (IRR) from periodic cash flows with an NPV cross-check.
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What is IRR Calculator?
An IRR (Internal Rate of Return) calculator finds the discount rate that makes the net present value of a series of periodic cash flows exactly zero. It is the standard metric for comparing projects, private equity returns, and investment performance accounting for the timing of every cash flow.
Key Benefits
- Time-value-of-money accuracy
- NPV cross-check verification
- Unlimited cash-flow periods
- Fast local computation
Common Use Cases
- •Capital budgeting decisions
- •Comparing investment projects
- •Private equity performance
- •Equipment purchase analysis
How to Calculate IRR
- Enter initial investment: Type the amount invested as a negative number (e.g. -10000).
- Add periodic returns: Enter each period cash flow as a positive number for money received.
- Add or remove periods: Use Add Period / remove buttons to match your project timeline.
- Read the IRR: See the solved rate, the NPV cross-check, and the total net gain.
Key Features
- Bisection IRR solver with convergence guarantee
- NPV cross-check at the solved rate
- Unlimited cash-flow periods
- Handles investments and mixed flows
- Copy-ready calculation summary
- Works offline in your browser
Frequently Asked Questions
What is IRR?
IRR (Internal Rate of Return) is the discount rate at which the net present value of a series of cash flows equals zero. It represents the per-period return the investment generates.
How is IRR calculated?
IRR is found numerically: this tool uses bisection, repeatedly halving an interval until the NPV at the midpoint is effectively zero, then verifies the result with an NPV cross-check.
What is a good IRR?
Compare IRR with your cost of capital or required rate of return (hurdle rate). A project adds value when IRR exceeds that threshold; the higher above it, the better.
Why does my cash flow series have no IRR?
A series needs at least one negative flow (investment) and one positive flow (return). Unconventional sign patterns can produce multiple IRRs or none — restructure flows per period if this happens.